Novel 4h-m-dithino[5, 4-d]pyrimidines



United States Patent 13 Claims. (31. 260-246) This invention relates to novel 4H-m-dithiino-[5,4-d] pyrimidine substitution products and acid addition salts thereof, as well as to various methods of preparing such compounds.

More particularly, the present invention relates to 4H- m-dithiino[5,4-d1pyrimidine substitution products of the formula wherein R and R which may be identical to or different from each other, are hydrogen, alkyl, haloalkyl, hydroxyalkyl, aminoalkyl, alkenyl, aryl or aralkyl, where the aromatic moiety of said aryl and aralkyl may have one or more halogen, lower alkyl, lower alkoxy, amino, monoalkylarnino or dialkylamino substituents attached thereto, or, together with each other and the carbon atom of the dithiino ring to which they are attached, form a to 7-membered spyrocyclic ring which may be interrupted by a sulfur or nitrogen atom,

R is hydrogen, alkyl, aryl, aralkyl, where the aromatic moiety of said aryl and aralkyl may have one or more halogen, lower allryl, lower alkoxy, amino, monoalkylalkoxy, alkenoxy, alkoxy-alkoxy, monoalkyl-arnino-alkoxy, dialkyl-amino-alkoxy, aralkoxy, alkylmercapto, carbalkoxyalkyl-mercapto, monoalkylaminoalkyl-mercaptO, diaikylaminoalkyl mercapto, aryl mercapto, aralkyl-mercapto or an amino group of the formula R5 I N I where R is hydrogen, amino, alkyl, hydroxyalkyl, alkoxyalkyl,

alkylthioalkyl, haloalkyl, aminoalkyl, monoalkylaminoall-:yl, dialkylaminoalkyl, alkenyl, cycloalkyl, aralkyl, aryl or pyridyl, and

R is alkyl, alkenyl or hydroxyalkyl, or

R and R together with each other and the adjacent nitrogen atom, form a basic heterocyclic ring which may comprise an additional heteroatom, such as oxygen, sulfur or nitrogen, and may have one or more alkyl or aryl substituents attached to the ring members, and

R is hydrogen, hydroxy, alkoxy, alkenoxy, alkoxy-alkoxy,

monoalkylamin'o alkoxy, dialkylamino alkoxy, aralkoxy, mercapto, alkylmercapto, carbalkoxyalkyl-mercapto, monoalkylaminoalkyl mercapto, dialkylaminoalkyl-mercapto, arylmercapto, aralkyl-mercapto, amino 3,3 l l,fi23 Patented Mar. 28, i957 where R and R have the meanings defined above, and non-toxic, pharmacologically acceptable acid addition salts thereof.

The compounds of the present invention may be prepared by a variety of methods involving well-known chemical principles. However, the following have proved to be most convenient and efficient:

METHOD A By reacting an m-dithian of the formula with a compound of the formula Z Rs C l IHg (III) or a tautomer thereof of the formula RsC IHIH (IV In Formulas II through IV, R R and R have the same meanings as in Formula I, X is a reactive, functional derivative of a carboxyl group, and Y and Z are oxygen or imino (:NH), provided, however, that Y and Z are not oxygen at the same time.

Examples of suitable reactive, functional derivatives of 5-oxoor S-imino-m-dithian carboxylic acid are their esters, nitriles, amidines, amides or thioamides.

Examples of suitable compounds of the Formula III or IV are O-alkyl-isoureas, S-alkyl-isothioureas, carboxylic acid amides and carboxylic acid amidines, such as formamide and formamidine, and substituted guanidines This method produces compounds of the Formula I wherein R R and R have the indicated meanings, and R is a free hydroxyl group, a free mercapto group or a free amino group. For instance, compounds of the Formula I wherein R is a free hydroxyl group are obtained when a compound of the Formula II is used wherein X is alkoxycarbonyl or aminocarbonyl; on the other hand, compounds of the Formula I wherein R is a free mercapto group are obtained by starting with a compound of the Formula II wherein X is aminothiocarbonyl; finally, compounds of the Formula I wherein R is a free amino group are obtained by starting with a compound of the Formula 11 wherein X is cyano or amidino.

The reaction between compounds II and III or IV is advantageously performed at temperatures between 20 and 200 0, preferably at a pH of 810, using equimolar amounts of the reactants, and in the presence of a solvent, such as water or ethanol. The selection of the reaction temperature depends largely upon the reactivity of the reactant of the Formula III or IV. Thus, while the reaction with an amidine, guanidine, O-alkyl-isourea or S-alkyl-isothiourea will proceed already at room temperature, the reaction mixture must be heated to as high as -200 C. in the case that the reactant is formamide, depending upon the reactivity of the functional derivative of the carboxylic acid of the Formula II.

The majority of m-dithian derivatives of the Formula II used as starting compounds in this method are known compounds and are described by Howard and Lindsey, J.A.C.S. 83, 158-164 (1960) and by Liittringhaus and Prinzbach, Liebigs Ann. Chem. 624, 7997 (1957). However, those which have heretofore not been specifically described may be prepared by the methods described in the above literature references. Thus, for instance, we were able to prepare the two novel compounds Z-methyl- 2benzyl-4-carbethoxy-m-dithianone-(5), which is a nondistillable oil, and 2-benzyl-4-carbethoxy-m-dithianonewhich has a melting point of 72 C.

METHOD B By reacting a 4H-m-dithiino[5,4-d]pyrimidine of the formula where R and R have the same meanings as in Formula I, with a compound of the formula R H R H (VII) wherein R is alkoxy, alkenoxy, alkoxy-alkoxy, monoalkylamino-alkoxy, dialkylamino-alkoxy, aralkoxy, alkylmercapto, carbalkoxyalkyl-mercapto, monoalkylaminoalkyl-mercapto, dialkylaminoalkyl-mercapto, arylmercapto, aralkylmercapto, amino or where R and R have the same meanings as in Formula I, and R is alkoxy, alkenoxy, alkoxy-alkoxy, monoalkylamino-alkoxy, dialkylamino-alkoxy, aralkoxy, alkylmercapto, carbalkoxyalkyl-mercapto, monoalkylaminoalkylr mercapto, dialkylaminoalkyl mercapto, arylmercapto, aralkylmercapto, amino or an -N E 1 where R and R have the same meanings as in Formula I;

Thus, if it is desired to use the present method for the preparation of a compound of the Formula I wherein R and R are identical, the starting compound should be one of the Formula V wherein both A, and A are halogen, mercapto or alkylmercapto; such a starting compound is then reacted with two or more molar equivalents of compound VI or VII.

On the other hand, if it is desired to use the present method for the preparation of a compound of the Formula I wherein R and R are different substituents, the substituent A may either first be exchanged for a radical R and substituent A is thereafter exchanged for a radical R or a starting compound of the Formula V may be used wherein A or A is already a radical other than halogen, mercapto or alkylmercapto, which is reacted with one or more molar equivalents of a compound of the Formula VI or VII.

bases. In those instances where either or both of radicals R and R in compounds VI and VII are of the formula R l -N as previously defined, an excess of at least one molar equivalent of compound VI or VII above and beyond the amount required for reaction with compound V may be used as the hydrogen halide-neutralizing agent. A still greater excess of the amine R H-N a Rs may also serve as the solvent medium for the reaction.

The optimum reaction temperature for the reaction pursuant to the present method depends largely upon the reactivity of the reactants. In general, if either or both of A and A are halogen, the exchange of these halogen atoms for a radical R or R in the presence of a hydrogen halideneutralizing agent proceeds at room temperature or moderately elevated temperatures. On the other hand, if either or both of A and A are mercapto or alkylmercapto, the exchange of these mercapto groups for the amino group R6" as previously defined, proceeds only at temperatures between and 200 C.

In the event that the solvent medium selected for the reaction has a low boiling point, or if an excess of the compound R7H or R H, respectively, is used as solvent medium, as described above, and this compound has a low boiling point, it is advantageous to perform the reaction in a closed vessel.

If it is desired to prepare a compound of the Formula I wherein R is a substituted hydroxyl or substituted mercapto group and/or R is a free or substituted hydroxyl group or a free or substituted mercapto group, it is advantageous to start with a compound of the Formula V wherein either or both of the substituents A and A are halogen. On the other hand, if it is desired to prepare a compound of the Formula I wherein R is alkyl, aryl or aralkyl, it is necessary to start with a compound of the Formula V wherein A is already alkyl, aryl or aralkyl.

The compounds of the Formula V used as starting materials in Method B may be prepared by Method A, supra. If it is desired to prepare compounds of the Formula V wherein either or both of substituents A and A are mercapto or alkylmercapto, they may be prepared directly by ring closure pursuant to Method A, for instance, by reacting a S-imino-m-dithian-4-carboxylic acid thioamide with a corresponding thiourea derivative.

Compounds of the Formula V wherein A and A are halogen may be prepared from 6,8-dihydroxy-4H-m-dithiino[5,4-d]pyrimidine, which is described in Ann. Chem. 49, 18444849 (1959), by reacting the latter with a phosphorus oxyhalide.

Compounds of the Formula V wherein only A is halogen may be obtained by reacting a compound of the Forfillllla I wherein R is hydroxy with a phosphorus oxyaide.

Examples A through X below illustrate the preparation of a number of compounds of the Formula V which may be used as starting compounds for Method B.

In those instances where Methods A and B yield a compound of the Formula I wherein either or both of substituents R and R are hydroxyl, mercapto or amino, which is always the case for R when the procedure of Method A is used, that compound may subsequently be transformed by customary methods into a corresponding compound wherein either or both of substituents R and R are any of the substituted hydroxyl, mercapto or amino groups included in the definition of R and R in connection with Formula I, for instance, by reacting the intermediate product with a reactive ester of a corresponding alcohol, especially with hydrohalic acid esters or sulfonic acid esters. It should be noted, however, that aryl and pyridyl radicals may not be introduced by this method.

In those cases where Method A or B yields a compound of the Formula I wherein either or both of substituents R and R are mercapto or substituted mercapto, these substituents may subsequently be converted into hydrogen by known methods, such as by hydrogenation in the presence of Raney nickel. As a matter of fact, compounds of the Formula I wherein R is hydrogen can he obtained only by this subsequent hydrogenation procedure.

Compounds of the Formula I which have one or more basic substituents attached to the fused'ring nucleus may, if desired, be converted into their non-toxic, pharmacologically acceptable acid addition salts by known methods, such as by dissolving the free base in a suitable solvent and acidifying the solution with one or more molar equivalents of the desired inorganic or organic acid. Examples of such acid addition salts are those formed with hydrochloric acid, sulfuric acid, phosphoric acid, acetic acid, critic acid, tartaric acid, maleic acid, S-chlorotheophylline and the like.

In addition, those compounds of the Formula I wherein R1 is a free hydroxyl or mercapto group may be converted into their alkali metal salts by customary methods.

The following examples further illustrate the present invention and will enable others skilled in the art to understand it more completely. It should be understood, however, that the invention is not limited to the particular illustrative examples given below.

Example A Preparation of 6-clzl0r0-8-m0rph0lino-4H-m-dillziino[5, 4-d]pyrimirline.0.8 cc. (0.0092 mol) of morpholine was added dropwise at room temperature to a vigorously agitated suspension of 1 gm. (0.0043 mol) of 6,8-dichloro- 4I-I-m'dithiino [5,4-d1pyrimidine in 10 cc. of absolute ethanol. A slight increase in temperature was observed, but dissolution of the suspended particles did not occur. After all of the morpholine had been added the reaction mixture was stirred at room temperature for one and a half hours more. Thereafter, the reaction mixture was vacuum filtered, and the filter cake was washed first with ethanol and water and was then recrystallized from ethanol. 0.7 gm. (58% of theory) of a crystalline com pound having a melting point of 181l82 C. was ob tained. It was identified to be 6-chloro-8-rnorpholino-4H- m-dithiino[5,4-d]pyrirnidine of the formula Analysis.C H CiN OS mol. wt. 289.82. Calculated: C, 41.44%; H, 4.17%; Cl, 12.24%. Found: C, 41.30%; H, 4.20%; Cl, 12.48%.

5 Example B Preparation of 6-m0rpholin0-8-chloro-4H-m-dithiino[5, 4-d]pyrimidine.-A mixture of 6.75 gm. (0.025 mol) of 6 morpholino 8 hydrox -4H-m-dithiirro[5,4-d]pyrimidine and 30 cc. of phosphorus oxychloride was refluxed for two hours. A clear solution was formed. The excess, unreacted phosphorus oxychloride was distilled olf in vacuo, and the viscous residue was decomposed with ice water and extracted several times with chloroform. The chloroform extract solutions were combined, the chloroform was evaporated in vacuo, and the yellowishbrown crystalline residue was recrystallized from ethanol. 6.0 gm. (83% of theory) of a product having a melting point of 129-131" C. were obtained, which was identified to be -morpholino-8-chl0ro-4H-m-dithiino[5,4-d]pyrimidine of the formula Analysis.C H ClN OS mol. wt. 289.82. Calculated: C, 41.44%; H, 4.17%; Cl, 12.24%. Found: C, 41.40%; H, 4.09%; Cl, 12.31%.

Using a procedure analogous to that described in EX- arnple B, the following additional 8-chlono-4H-m-dithiino[5,4-d]pyri1nidines of the Formula V above were prepared with the aid of phosphorus oxychloride:

Example C 6-(2 -methylmorpholino 8 chloro-4H-m-dithiir1o[5, 4-d]pyrmidine, MP. 9394 C. (recrystallized from ethanol), from 6-(2 methylmorpholino)-8-hydroxy-4H-m-dithiino[5,4-d]pytrmidine. The yield was 74% of theory.

Example D 6 pyrro'lidino 8 chloro-4H-m-dithiino[5,4-d]pyrimidine, MP. 91 C. (recrystallized from gasoline), from 6-pyrrolidino 8 hydroxy-4H-dithiino[5,4-d]pyrimidine. The yield was 77% of theory.

Example E 6 methyl-8-chlo-ro-4I-I-m-dithiino[5,4-d]pyrimidine, a non-disti-llable oil, from 6-1nethyl-8-hydr0xy-4H-m-dithiino[5,4-d]pyrirnidine. The yield was 74% of theory.

Example F 6-n-propyl-8-chloro-4H-m-dithiino[5,4 d]pyrimidine, a non-distillable oil, from 6-n-propyl-8-hydroxy-4H-m-dithiino[5,4-d]pyrimidine. The yield was 64% of theory.

Example G 6-isopropy1 8 chloro-4H-m-dithiino[5,4-d1pyrimidine, a non-distillable oil, for 6-isopropyl-8-hydroxy-4H-m-dithiino[5,4-d] pyrimidine. The yield was 90% of theory.

Example H 6-n-pentyl 8 chloro-4H-m-dithiino[5,4-d]pyrimidine, a non-distillable oil, from 6-n-pentyl-8-hydroxy-4H-m-di- -thiino[5,4-d]pyrimidine. The yield was 90% of theory.

Example I 6-phenyl 8 chloro-4H-m-dithiino[5,4-d1pyrimidine, a non-distillable oil, from 6-phenyl-8-hydroxy-4H-m-dithiino [5,4-d] pyrimidine. The yield was 79% of theory.

Example J Z-methyl 6-pyrrolidino 8-chloro 4H-m-dithiino [5, 4-d] pyrimidine, a non-distillable oil of the formula l or from Z-methyl 6-pyrrolidino 8-hydroXy-4H-m-dithiino [5,4-d]pyrimidine. The yield was 84% of theory.

Example K Z-methyl 6-morpholino 8-chloro 4H-m-dithiino[5, 4-d]pyrimidine, M.P. 140 C. (recrystallized from ethylacetate), from 2-methyl-6-morpholino 8-hydroxy-4H-mdithiino[5,4-d] pyrimidine. The yield was 71% of theory.

Example L 2,6-dimethyl 8-chloro 4H-m-dithiino[5,4-d]pyrimidine, a non-distillable oil, from 2,6-dirnethyl-8-hydroxy- 4H-rn-dithiino[5,4-d] pyrimidine. The yield was 82% of theory.

Example M 2-methy1 6-ethyl 8-chloro 4Hrn-dithiino[5,4-d] pyrimidine, a non-distillable oil, from 2-methyl-6-ethyl-8- hydroxy-4H-m-dithiino[5,4-d]pyrimidine. The yield was 84% of theory.

Example N 2 methyl-6-n-propyl 8 chloro-4H-m-dithiino[5,4-d] pyrimidine, a non-distillable oil, from 2-methyl-6-n-propyl- S-hydroxy 4H-m-dithiino[5,4-d1pyrimidine. The yield was 81% of theory.

Example 2-phenyl 6-pyrrolidino 8-chloro-4H-m-dithiino[5,4-d]

pyrimidine, a non-distillable oil of the formula from 2-phenyl-6-pyrrolidino 8-hydroxy 4H-m-dithiin0 [5,4-d] pyrimidine. The yield was 90% of theory.

Example P Z-phenyl fi-morpholino 8-chloro 4H-m-dithiino[5, 4-d]pyrimidine, M.P. 147148 C. (recrystallized from ethylacetate), from 2-phenyl-6-morpholino-8-hydroxy4I-I- m-dithiino[5,4-d] pyrimidine. The yield was 57% of theory.

Example Q 2-phenyl 6 methyl 8 chloro-4H-m-dithiino[5,4-d] pyrimidine, a non-distillable oil, from 2-phenyl-6-methyl- 8-hydroxy 4H-m-dithiino[5,4-d1pyrimidine. The yield was 60% of theory.

Example R 2-phenyl-6-n-propyl-8-chloro-4H m dithiino[5,4 d] pyrimidine, a non-distillable oil, from 2-phenyl-6-propyl- 8-hydroxy-4H m dithiino[5,4-d] pyrimidine. The yield was 80% of theory.

Example S 6-ethyl-8-chloro 4H m dithiino[5,4-d] pyrimidine, a non-distillable oil, from 6-ethyl-8-hydroxy-4H-m-dithiino [5,4-d] pyrimidine. The yield was 83% of theory.

Example T 6-benzyl-8-chloro-4H m dithiino[5,4 d]pyrimidine, M.P. 136137 C. (recrystallized from ethylacetate), of

from 6 benzyl 8-hyd-r0xy-4H-m-dithiino[5,4-d1pyrimidine. The yield was 78% of theory.

6,8-dichloro-4H n1 dithiino[5,4-d1pyrimidine, M.P. 121-1225 C. (recrystallized from petroleum ether), of

the formula Cl( I l from 6,8 dihydr-oxy 4H m-dithiino[5,4-d] pyrimidine. The yield was 48% of theory.

Example X 6-ethylmercapto-S-chloro-4H-m-dithiino[5,4 d]pyrimidine, M.P. 8l82 C. (recrystallized from ethanol), of the formula from 6-ethylmercapto-8-hydroxy-4H-m-dithiino[5,4 d] pyrimidine. The yield Was 78% of theory.

Example 1 Preparation of 6-ell1ylmercapro-8-lzydr0xy-4Hm-ditl1ii[5,4-d]pyrimidine by [Method A.-20. 6 gm. (0.1 mol) of 4-carbethoxy-5-m-dithianone were added dropwise at room temperature to an agitated solution of 18.5 gm. (0.1 mol) of S-ethylisothiourea hydrobromide and 13.8 gm. (0.1 mol) of potassium carbonate in 100 cc. of water. The reaction product began to precipitate after a short period of time. After all of the dithianone had been added, the reaction mixture was stirred at room temperature for eight hours more. Thereafter, the reaction mixture was vacuum filtered, and the filter cake was washed with water and was then recrystallized from ethanol. 22.5 gm. (91% of theory) of a white crystalline compound having a melting point of 226-227 C. were obtained, which was identified to be the compound of the formula N cans-f C, 39.00%; H, 4.09%; N, 11.37%; S, 39.04%. Found: C, 38.90%;1-1, 4.14%; N, 11.23%; S, 38.98%.

Example 2 Preparation of 6-merlz0xy 8 lzyzlroxy-4H-m-dillziin0 [5,4-d1pyrimidine by lWet/zod A.11.6 gm, (0.105 mol) of O-methylisourea hydrochloride were added, while stirring, to a solution of 2.4 gm. (0.105 gm.-atoms) of sodium in 75 cc. of absolute ethanol which had been cooled to +10 C. The mixture was allowed to stand for 15 minutes, and then gm. (0.07 mol) of 4-carbethoxym-dithianone-(S) were added dropwise at 10 C., whereby a heavy precipitate was formed immediately. In order to bring the reaction to completion, the reaction mixture was then stirred for hours at room temperature. Thereafter, the precipitate, was separated by vacuum filtration, washed with water and recrystallized from a mixture of butanol and dimethylformamide. 6.5 gm. (43% of theory) of a substance having a melting :point of 239- 240" C. were obtained. It was identified to be the compound of the formula AnaIysis.C H N O S mol, wt. 216.29. Calculated: C, 38.87%; H, 3.73%; N, 12.95%. Found: C, 38.93%; H, 3.83%;N, 12.75%.

Example 3 Preparation of 6-pyrrolidino-8-hydroxy-4H-m-dithiino- [5,4-d]pyrimidine by Method A.15.0 gm. (0.1 mol) of N,N-tetramethylene-guanidine hydrochloride and 20.6 gm. 0.1 mol) of 4-carbethoxy-S-m-dithianone were added to a solution of 2.3 gm. (0.1 gm.-atorns) of sodium in cc. of absolute ethanol. The resulting mixture was then stirred for half an hour at room temperature and subsequently for five hours at reflux temperature. Thereafter, the reaction mixture was allowed to cool, and the precipitate formed thereby was separated by vacuum filtration, washed with water and recrystallized from dimethylformamide. 18.1 gm. (71% of theory) of a substance having a melting point of 286287 C. were obtained. It was identified to be the compound of the formula Analysis.C H N OS mol. wt. 255.37. Calculated: C, 47.03%; H, 5.13%; N, 16.46%. Found: C, 47.17%; H, 5.12%; N, 16.42%.

Example 4 Using a procedure analogous to that described in Example 1, 2-methyl-6-ethylmercapto-8-hydroxy-4H-m-dithiino[5,4-d]pyrimidine, M.P. 189-190 C. (recrystallized from dimethylformamide), of the formula was prepared from S-ethylisothiourea hydrobromide and 2-methyl-4-carbethoxy-m-dithianone-(5). The yield was 69% of theory.

Example 5 Using a procedure analogous to that described in Example 1, Z-phenyl-6-ethylmercapto-8-hydroxy-4H-m-dithiino[5,4-d]pyn'midine, M.P. 260-262 C. (recrystallized from ethyl glycol), of the formula was prepared from Sethylisothiourea hydrobromide and 2-phenyl-4-carbethoxy-rn-dithianone-(5). The yield was 73% of theory.

Example 6 Using a procedure analogous to that described in Example 2, Z-methyl-6-methoxy-8-hydroxy-4H-m-dithiino- 10 [5,4-d]pyrimidine, M.P. 229-230" C. (recrystallized from butanol), of the formula was prepared from O-methylisourea hydrochloride and 2- methyl-4-carbethoxy-m-dithianone-(5). The yield was 45% of theory.

Example 7 Using a procedure analogous to that described in Example 2, 8-hydroxy-4H-m-dithiino[5,4-d] pyrimidine, M.P. 245247 C. (recrystallized from butanol), of the formula was prepared from formamidine hydrochloride and 4- carbethoxy-m-dithianone-(S). The yield was 64% of theory.

Example 9 Using a procedure analogous to that described in Example 2, 6 -methyl-8-hydroxy-4H-rn-dithiino 5,4-d] pyrimidine, M.P. 281-283 C. (recrystallized from dimethylformamide), of the formula omf wl j W was prepared from acetamidine hydrochloride and 4- carbethoxy-m-dithianone-(5). The yield was 59% of theory.

Example 10 Using a procedure analogous to that described in Example 2, 6-ethyl-8-hydroxy-4H-m-dithiino[5,4-d] pyrimidine, M.P. 270-272 C. (recrystallized from butanol), was prepared from propionamidine hydrochloride and 4-carbethoxy-m-dithianone-(S). The yield was 67% of theory.

Example 11 Using a procedure analogous to that described in EX- ample 2, 6-n-propyl-8-hydroxy-4H-m-dithiino[5,4-cl]pyrimidine, M.P. 223227 C. (recrystallized from ethanol), was prepared from n-butyramidine hydrochloride and 4- carbethoxy-m-dithianone-(5). The yield was of theory. 7

Example 12 Using a procedure analogous to that described in Example 2, 6-isopropyl-8-hydroxy-4H-m-dithiino[5,4-d]pyrimidine, M.P. 269270 C. (recrystallized from dimethylformamide), was prepared from isobutyramidine hydrochloride and 4-carbethoxy-m-dithianone-(5). The yield was 62% of theory.

Example 13 Using a procedure analogous to that described in Example 2, 6-n-butyl-8-hydroxy-4H-m-dithiino[5,4-d1pyrimidine, M.P. 176 C. (recrystallized from methal nol), was prepared from n-valerami-dine hydrochloride and 4-carbethoxy-m-dithianone-(5). The yield was 53% of theory.

Example 14 Using a procedure analogous to that described in Example 2, Z-methyl-8-hydroXy-4H-m-dithiino[5,4-d1pyrimidine, M.P. 2l4216 C. (recrystallized from ethanol), of the formula was prepared from formamidine hydrochloride and 2- methyl-4-carbethoxy-m-dithianone-(5). The yield was 70% of theory.

Example 15 Using a procedure analogous to that described in EX- ample 2, 2,6-dirnetl1yl-S-hydroxy-4-H-m-dithiino[5,4-d]pyrimidine, M.P. 255257 C. (recrystallized from dimethylformamide), of the formula was prepared from acetamidine hydrochloride and 2-methyl-4-carbethoXy-m-dithianone-(5 The yield was 50% of theory.

Example 16 Using a procedure analogous to that described in EX- ample 2, 2-methyl-6-ethyl-8-hydroxy-4H-m-dithiino[5,4- dJpyrirnidine, M.P. 217218 C. (recrystallized from propanol), was prepared from propionamidine hydrochloride and 2-methyl-4-carbethoXy-m-dithianone-(5). The yield was 49% of theory.

Example 17 Using a procedure analogous to that described in EX- ample 2, methyl-6-isopropyl-S-hydroXy-4H-m-dithiino [5,4-d1pyrimidine, M.P. 21'72l9 C. (recrystallized from ethanol), was prepared from isobutyramidine hydrochloride and 2-methyl-4carbethoxy-m-dithianone-(5). The yield was 58% of theory.

Example 19 Using a procedure analogous to that described in Example 2, 2-methyl-6-n-butyl-8-hydroXy-4H-rn-dithiino[5, 4-d]pyrimidine, M.P. 198-200 C. (recrystallized from acetone), was prepared from n-valeramidine hydrochloride and 2-methyl-4-carbethoXy-rn-dithianone-(5). The yield was 73% of theory.

Example 20 Using a procedure analogous to that described in Example 2, Z-phenyl-6-methyl-8-hydroxy-4I-I-m-dithiino[5, 4-d]pyrimidine, M.P. 283-285 C. (recrystallized from dimethylformamide), was prepared from acetamidine hydrochloride and 2-phenyl-4-carbethoXy-n-dithianone-(5). The yield was 61% of theory.

Example 21 Using a procedure analogous to that described in EX- ample 2, 2-phenyl-6-ethyl-8-hydroxy-4H-m-dithiino[5,4- d]pyrimidine, M.P. 269-270 C. (recrystallized from di- 12 methylforrnamide), was prepared from propionamidine hydrochloride and 2-phenyl-4-carbethoXy-rn-dithianone- (5). The yield was 74% of theory.

Example 22 Using a procedure analogous to that described in EX- ample 2, 2-phenyl-6-n-propyl-S-hydroxy-4H-m-dithiino[5, 4-d]pyrirnidine, M.P. 28l-283 C. (recrystallized from ethylglycol), was prepared from n-butyramidine hydrochloride and 2 phenyl 4 carbethoxy-m-dithianone-(5 The yield was 87% of theory.

Example 23 Using a procedure analogous to that described in EX- ample 2, 2-phenyl6-isopropyl-8-hydroxy-4H-m-dithiino [5,4-d]pyrimidine, M.P. 274276 C. (recrystallized from dimethylformamide), was prepared from isobutyramidine hydrochloride and Z-phenyl-4-carbethoxy-m-dithianone- (5). The yield was 78% of theory.

Example 24 Using a procedure analogous to that described in Example 2, 2-phenyl-6-n-butyl-S-hydroXy-4H-m-dithiino[5, 4-d]pyrimidine, M.P. 225227 C. (recrystallized from ethylglycol), was prepared from n-valeramidine hydrochloride and 2 phenyl 4 carbethoxy1n-dithianone-(5 The yield was 75% of theory.

Example 25 Using a procedure analogous to that described in Example 2, 6-n-pentyl-8-hydroxy-4H-m-dithiino[5,4-d]pyri'midine, M.P. 177179 C. (recrystallized from ethanol), was prepared from n-capramidine hydrochloride and 4- carbethoxy-m-dithianone-(5). The yield was 67% of theory.

Example 26 Using a procedure analogous to that described in EX- ample 2, 6 n hexyl-8-hydroxy-4H-m-dithiino[5,4-d] pyrimidine, M.P. 143l44 C. (recrystallized from ethanol), Was prepared from n-enantharnidine hydrochloride and 4-carbethoXy-m-dithianone-(5). The yield was 61% of theory.

Example 27 Using a procedure analogous to that described in EX- ample 2, 6 phenyl-S-hydroxy-4H-m-dithiino[5,4-d] pyrimidine, M.P. 270 C. (recrystallized from methylglycol), was prepared from benzamidine hydrochloride and 4-carbethoXy-m-dithianone-(5). The yield was 40% of theory.

Example 28 Using a procedure analogous to that described in Example 3, 2 methyl-6-pyrrolidino-S-hydroxylH-m-dithiino[5,4-d1pyrimidine, M.P. 265266 C. (recrystallized from methylglycol), of the formula was prepared from N,N-tetramethylene-guanidine hydrochloride and 2-methyl-4-carbethoxy-m-dithianone-(5). The yield was 54% of theory.

Example 29 Using a procedure analogous to that described in Example 3, 2 methyl-G-morpholino-8-hydroxy-4H-m-dithiino[5,4-d]pyrimidine, M.P. 268270 C. (recrystallized from methylglycol), of the formula was prepared from N,N-diethyleneoXy-guanidine hydrochloride and 2-rnethyl-4-carbethoxy-m-dithianone-(5). The yield was 72% of theory.

Example 30 Using a procedure analogous to that described in EX- ample 2, 2 methyl-6-phenyl-S-hydroxy-4Hrn-dithiino [5,4-d] pyrimidine, M.P. 269271 C. (recrystallized from methylglycol), of the formula UV Q was prepared from benzamidine hydrochloride and 2- phenyl-4-carbethoXy-rn-dithianone-(5). The yield was 65% of theory.

Example 32 Using a procedure analogous to that described in Example 1, 2,2 dirnethyl-6-ethylmercapto-8-hydroxy-4H- m-dithiino[5,4-d]pyrirnidine, M.P. 2l72l9 C. (recrystallized from ethanol), of the formula N classs N k Ha I O H was prepared from S-ethylisothiourea hydrobromide and 2,2-dirnethy1-4-carbethoxy-m-dithianone-(5). The yield was 66% of theory.

Example 33 Using a procedureanalogous to that described in EX- arnple 1, 2-methyl 2 benzyl-6-ethylmercapto-8-hydroxy-4H-rn-dithiino{5,4-d1pyrirnidine, M.P. 226-228 C. (recrystallized from methylglycol), of the formula cans-( S N I C Ha W Q was prepared from Sethylisothiourea hydrobromide and 2-methyl 2 benzyl 4 carbethoXy-rn-dithianone-(5). The yield was 36% of theory.

Example 34 Using a procedure analogous to that described in EX- arnple 2, 6-benzyl 8 hydroxy-4H-m-dithiino[5,4-d] pyrimidine, M.P. 250252 C. (recrystallized from methylglycol), of the formula M- was prepared from phenylacetamidine hydrochloride and 4-carbethoxy m-dithianone-(5). The yield was 43% of theory.

Example Using a procedure analogous to that described in Example 2, 2-methyl 2 phenyl-6-benzyl-8-hydroxy-4H- m-dithiino[5,4-d]pyrimidine, M.P. 217218 C. (recrystallized from ethanol), was prepared from phenylacetarnidine hydrochloride and 2-methyl-2-phenyl-4-carbethoxym-dithianone-(S). The yield was 56% of theory.

Example 36 Using a procedure analogous to that described in EX- arnple 2, 2,2-dimethyl-6-n-propyl 8 hydroXy-4H-mdithiino[5,4-d]pyrimidine, M.P. 213214 C. (recrystallized from ethanol), was prepared from n-butyramidine hydrochloride and 2,2-dirnethyl-4-carbethoxy-m-dithianone-(5). The yield was of theory.

Example 37 Using a procedure analogous to that described in EX- ample 2, 2-rnethyl-6-n-hexyl-8-hydroXy-4H-rn-dithiino [5,4- d]pyrirnidine, M.P. 156-157 C. (recrystallized from ethanol), of the formula Was prepared from enanthamidine hydrochloride and 2- methyl-4-carbethoxy-m-dithianone-(5). The yield was 68% of theory.

Example 38 Using a procedure analogous to that described in Example 3, 2-methyl-6-n-hexylamino-8-hydroxy-4H-rndithiino[5,4-d]pyrimidine, M.P. 174-175 C. (recrystallized from butanone), of the formula was prepared from N-n-heXy-l-guanidine hydrochloride and 2-methyl-4-carbethoXy-rn-dithianone-(5). The yield was 54% of theory.

Example 39 Using a procedure analogous to that described in Example 2, 2-isopropyl-6-methyl-8-hydroxy-4H-rn-dithiino [5,4-d] pyrimidine, M.P. 226-227" C. (recrystallized from ethanol), was prepared from acetarnidine hydrochloride and 2 isopropyl-4-carbethoxy m dithianone-(S The yield was 48% of theory.

Example 40 Using a procedure analogous to that described in EX- ample 2, 2-isopropyl-6-n-propyl-8-hydroXy-4H-rn-dithiino [5,4d1pyrimidine, M.P. 208-209 C. (recrystallized from ethanol), was prepared from n-butyramidine hydrochloride and 2-isopropyl-4-carbethoxy-m-dithianone-(5). The yield was 56% of theory.

Example 41 Using a procedure analogous to that described in EX- ample 2, 2-isopropyl-6-benzyl-8-hydroXy-4H-rn-dithiino [5,4djpyrirnidine, M.P. 245-246 C. (recrystallized from methylglycol), was prepared from phenylacetarnidine hydrochloride and 2-isopropyl-4-carbethoxy-m-dithianone- (5).

Example 42 Using a procedure analogous to that described in EX- ample 2, 6' methyl-8'-hydroXy-spiro[cycloheXane-l,2'-

(4H-m-dithiino[5,4-d]pyrimidine)1, MP. 270-27l C. (recrystallized from ethanol), of the formula ClIawas prepared from acetamidine hydrochloride and spiro- (cyclohexane 1,2) 4 carbethoxy-m-dithianone-(5). The yield was 39% of theory.

Example 43 Using a procedure analogous to that described in Example l, fi-ethylmercapto-8-hydroxy-spiro[(4H'n-dithiino [5,4-d]pyrimidine)2-3'-tetrahydrothiophene], M.P. 207 209 C. (recrystallized from ethanol), of the formula Using a procedure analogous to that described in Example 3, 6-morpholino-8-hydroxy-spiro(4H-m-dithiino[5, 4 djlpyrimidine 2,3-tetrahydrothiophene), M.P. 252 253 C. (recrystallized from dimethylformamide), of the formula was prepared from N,N-diethyleneoxy-guanidine hydrochloride and spiro (2',3 tetrahydrothiophene)-4carbethoxy-m-dithianone-(5). The yield was 53% of theory.

Example Preparation of 6 morplzolino 8 pyrrolidinolH-mdillziino[5,4-d]pyrimidine by Met/rod B.A mixture of 3.0 gm. (0.01 mol) of 6-ethylmercapto-8-pyrrolidino4l-lm-dithiino[5,4-d]pyrimidine and cc. of morpholine was heated for 30 hours at 175 C. in a closed vessel. v

Thereafter, the mixture was allowed to cool and was then poured into water, whereby a crystalline precipitate formed. The precipitate was separated by vacuum filtration, washed with water and recrystallized from ethanol.

2.1 gm. of theory) of a substance having a n1elt- I ing point of 145-146" C. were obtained. It was identified to be the compound of the formula Analysis.-C H N OS mol. wt. 324.47. Calculated: C, 51.82%; H, 6.21%; N, 17.27%. Found: C, 52.00%; H, 6.25%; N, 17.46%.

Example 46 Preparation of 6-morpholin0-8-l1ydr0xy-4H-m-ditlziino [5,4-d]pyrimirline by llletlzod B.A mixture of 5 gm. (0.02 rnol) of 6-ethylmercapto-8-hydroxy-4H-rn-dithiino [5,4-d]pyrimidine and 50 CC. of morpholine was refluxed .on an oil bath (bath temperature 140 C.) for eight hours,

Example 47 Using a procedure analogous to that described in Example 46, 6-(2'-methyl-morpholino)-8-hydroxy-4H-m-dithiino[5,4-dlpyrimidine, M.P. 284285 C. (recrystallized from dimethylformamide), of the formula 271.37. Calcu- Found: C,

was prepared from 6-ethylmercapto-8-hydroxy-4H-mdithiino[5,4-d]pyrimidine and Z-methyl-morpholine. The yield was 77% of theory.

Example 48 Using a procedure analogous to that described in Example 46, 2-phenyl-6-pyrrolidino-S-hydroxy-4H-m-dithiino[5,4-d]pyrimidine, M.P. 270 C. (recrystallized from methylglycol), of the formula was prepared from Z-phenyl-6-ethylmercapto-S-hydroxy- 4H-m-dithiino[5,4-d]pyrirnidine and pyrrolidine. The yield was 61% of theory.

Example 49 Using a procedure analogous to that described in xample 46, 2-phenyl-6-morpholino-8-hydroxy-4H-m-dithiino[5,4-d]pyrimidine, MP. 280 C. (recrystallized from methylglycol), was prepared from 2-phenyl-6-ethylmercapto-8-hydroxy-4H-m-dithiino [5,4-d] pyrimidine and morpholine. The yield was 65% of theory.

Example 50 Preparation of 6-pyrr0lidilz0 8 morpholino-4H-m-dir/ziino[5,4-zl1pyrzmidine by Method B.A mixture of l gm. (0.0034 mol) of 6-chloro-8-morpholino-4H-m-dithiino[5,4-d]-pyrimidine and 15 cc. of pyrrolidine was refluxed for four hours. Thereafter, the clear reaction solution was allowed to cool and was then poured into cc. of water. The crystalline precipitate formed thereby was separated by vacuum filtration, washed first with water and then with ethanol, and finally recrystallized from ethanol. 0.8 gm. (71% of theory) of a substance having a melting point of 133-l34 C. was obtained, which was identified to be the compound of the formula 17 Analysis.C H N OS mol. wt. 324.47. Calculated: C, 51.82%; H, 6.21%; N, 17.27%. Found: C, 51.90%; H, 6.28%; N, 17.07%.

Example 51 Preparation of 6-ethylmercapt0-8-pyrrolidino-4H-m-dithiino[5,4-d]pyrimidine by Method B.1 gm. (0.0038 mol) of 6-ethylmercapto-8-chloro-4H-m-dithiino[5,4-d] pyrimidine was added to 2 cc. (0.024 mol) of pyrrolidine. A vigorous reaction took place, accompanied by reflux and formation of a solution. The reaction solution was allowed to stand at room temperature and without application of heat for one hour. The crystalline precipitate formed during that time was then separated by vacuum filtration, and the filter cake was recrystallized from ethanol. 0.8 gm. (70% of theory) of a substance having a melting point of 104-105 C. was obtained, which was identified to be the compound of the formula Analysis.C H N S mol. wt. 299.49. Calculated:

C, 48.12%; H, 5.72%; S, 32.19%. Found: C, 48.20%; H, 5.83%; S, 31.90%.

Example 52 Preparation of 6,8 dimorpholino-4H-m dithiin[5,4-d] pyrimidine by Method B.A mixture of 5.8 gm. (0.02 mol) of 6-morpholino-8-chloro-4H m dithiino[5,4 d] pyrimidine and 15 cc. of morpholine was refluxed on an oil bath (bath temperature 150 C.) for three hours. Thereafter, the reaction mixture was allowed to cool, and then ether was added thereto. The precipitate formed thereby was separated by vacuum filtration, washed with water and recrystallized from ethanol. 5.4 gm. (79% of theory) of a substance having a melting point of 126 C. were obtained, which was identified to be the compound of the formula Analysis.C .,H N,O S mol wt. 340.47. Calculated: C, 49.38%; H, 5.92%; N, 16.46%. Found: C, 49.30%; H, 6.04%; N, 16.56%.

Example 53 Preparation of 6-morpholino 8 amin0-4H-m-dithiin0 [5,4-d1pyrimidine by Method B.A mixture of 5.8 gm. (0.02 mol) of 6-morpholino-8 chloro 4H m dithiino [5,4-d]pyrimidine and 50 cc. of liquid ammonia was heated for five hours in a closed vessel on an oil bath (bath temperature 100 C.). Thereafter, the reaction mixture was allowed to cool to room temperature, and then the excess ammonia was allowed to escape from the vessel. The crystalline residue was stirred with water, the aqueous mixture was vacuum filtered, and the filter cake was recrystallized from ethanol. 4.1 gm. (76% of theory) of a substance having a melting point of 138- 1% 139 C. were obtained. It was identified to be the conipound of the formula Analysis.C H N OS mol. wt. 270.39. Calculated: C, 44.42%; H, 5.22%; N, 20.72%. Found: C, 44.58%; H, 5.35%; N, 20.87%.

Example 54 Preparation of 6 -morpholino-8-ethanolamino-4H-mdithiino[5,4-d1pyrimidine by Method B.A mixture of 5.8 gm. (0.02 mol) of 6-morpholino-8-chloro-4H-m-dithiino[5,4-d]pyrimidine and 15 cc. of ethanolamine was heated for two hours on an oil bath (bath temperature 150 C.). Thereafter, the reaction solution was allowed to cool. The precipitate which crystallized out during that time was separated by vacuum filtration, washed first with ether and then with water, and recrystallized from etha.n 01. 3.5 gm. (58% of theory) of a substance having a melting point of -146 C. were obtained. It was identified to be the compound of the formula Analysis.C H N O S mol. wt. 314.44. Calculated: C, 45.84%; H, 5.77%; N, 17.82%. Found: C, 45.80%; H, 5.87%; N, 17.98%.

Example 55 Preparation of 6-phenyl-8-morpholino-4H-m-dithiino- [5,4-d1pyrimidine by Method B.A mixture of 3.7 gm. (0.013 mol) of 6-phenyl-8-chl0ro-4H-m-dithiino[5,4-d]- pyrimidine and 10 cc. of morpholine was refluxed for 24 hours. Thereafter, the excess, unreacted morpholine was distilled off under reduced pressure, and the residue was taken up in 30 cc. of 2 N hydrochloric acid. The acid solution was then extracted twice with 25 cc.-portions of ether, and the aqueous phase was made alkaline with ammonia. The oily precipitate formed thereby was taken up in chloroform, and the resulting solution was washed with water and then dried over sodium sulfate. The chloroform was distilled off, leaving a viscous residue which crystallized throughout upon being scratched. The crystalline mass was vacuum filtered, and the filter cake was recrystallized twice from ethylacetate. 1.8 gm. (41% of theory) of a substance having a melting point of 103 C. were obtained. It was identified to be the compound of the formula Q? \l l Analysis.-C H N OS mol. wt. 331.47. Calculated:

C, 57.97%; H, 5.17%; N, 12.68%. Found: C, 58.10%; H, 5.21%;N, 12.90%.

Example 56 Preparation of Z-methyZ-6-n-propyl-8-morphoZino-4H- m-dithiino[5,4-d1pyrimidine and its maleate by Method B.A mixture of 8.4 gm. (0.0032 mol) of 2-methyl-6-npropyl-8-chloro-4H-m-dithiino[5,4-d]pyrimidine and 20 cc. of morpholine was refluxed for 24 hours. Thereafter,

the excess, unreacted morpholine was distilled off under reduced pressure, and then the semi-solid residue was acidified with 2 N hydrochloric acid. The acid solution was extracted twice with 20 cc.-portions of ether, and the aqueous phase was made alkaline with sodium hydroxide. The oily precipitate formed thereby was taken up in ether, and the resulting solution was washed with water and dried over sodium sulfate. The ether was evaporated, leaving 6.85 gm. of an oily residue, which was identified to be raw 2-methyl-6-n-propyl-8-morpholino-4H-m-dithiino[5,4-d] pyrimidine of the formula This oily residue was dissolved in a small amount of absolute ethanol, and the resulting solution was admixed with 22 cc. of a 1M ethanolic solution of maleic acid. The ethanol was then evaporated, leaving a crystalline residue which was recrystallized several times from absolute ethylacetate. gm. (37% of theory) of the maleate of 2 methyl-6-n-propyl-8-morpholino-4H-m-dithiino[5,4- d]pyrimindine were obtained. It had a melting point of 94-95 C.

Analysis.C I-I N O S mol. wt. 427.55. Calculated: C, 50.57%; H, 5.89%; N, 9.83%; S, 15.00%. Found: C, 50.40%; H, 5.97%; N, 9.54%; S, 14.70%.

Example 57 Using a procedure analogous to that described in Exampl 54, 6-rnorpholino-8-(2-methyl-morpholino)-4H-m-dithiino[5,4-d]pyrimidine, M.P. l08109 C. (recrystallized from ethanol), was prepared from 6-morpholino-8-chloro- 4H-m-dithiino [5,4-d] pyrimidine and 2 methyl morpholine. The yield was 64% of theory.

Example 58 Using a procedure analogous to that described in EX- ample 54, 6-morpholino-8-(4-methyl-piperazino)-4H-mdithiino[5,4-d1pyrimidine, M.P. 124-125" C. (recrystallized from ethanol), of the formula was prepared from 6-morpholino-8-chloro-4H-m-dithiino- [5,4-d] pyrimidine and N-methyl-piperazine. The yield was 59% of theory.

Example 59 Using a procedure analogous to that described in EX- ample 54, 6-morpholino-8-piperidino-4H-m-ditl1iino[5,4- d]pyrimidine, M.P. 115-116" C. (recrystallized from ethanol), of the formula dithiino[5,4-d]pyrimidine and mor-pholine.

20 was prepared from 6-morpholino-8-chloro-4H-m-dithiino- [5,4-d]pyrimidine and piperidine. The yield was 72% of theory.

Example 60 Using a procedure analogous to that described in Example 54, 6-morpholino-8-pyrrolidino-4H-m-dithiino[5,4- d] pyrimidine, M.P. -146 C. (recrystallized from ethanol). was prepared from 6rnorpholino-8-chloro-4H- 'm-dithiino[5,4-d] pyrimidine and pyrrolidine. The yield was 61% of theory.

Example 61 Using a procedure analogous to that described in Example 52, 6-(2'-methyl-monpholino)-8-morpholino-4H- m-dithiino[5,4-d]pyrimidine, M.P. 117ll8 C. (recrystallized from acetone), was prepared from 6-(2-methylmorpholino) 8-chloro-4H-m-dithiino[5,4-d]pyrimidine and morpholine. The yield was 52% of theory.

Example 62 Using a procedure analogous to that described in Example 52, 6-pyrrolidino-8-morpho1ino-4H-m-dithiino[5,4- d]pyrimidine, M.P. l33l34 C. (recrystallized from acetone), was prepared from 6 pyrrolidino'8-chloro-4H-rn- The yield was 73 of theory.

Example63 Using a procedure analogous to that described in Example 54, 6-m0rpholino-8-cyclohexylamino-4H-m-ditl1iin0[5,4-d] pyrimidine, M.P. 128-l29 C. (recrystallized from ethanol), of the formula was prepared from 6-mor pholino-8-chloro-4H- m-dithiin0 [5,4-d]pyrimidine and cyclohexylamine. The yield was 50% of theory.

Example 66 Using a procedure analogous to that described in Example 54, 6-morphol ino-8-anilino-4Hi-m-dit-hiin0[5,4-d{] pyrimidine, M.P. 189-l90 C. (recrystallized from buta- 1101), of the formula was prepared from 6morpholino-8-chloro-4H- -ditl1iino [5,4-d]pyrimidine and aniline. The yield was 69% of theory.

21 Example 67 Using a procedure analogous to that described in Example 54, 6-morpholino-8-benzylamino-4H-m-dithiino [5,4-d]pyrimidine, M.P. 170-l7l C. (recrystallized from dimethylformarnide), of the formula was prepared from 6-rnorpholino-8-chloro-4H-m-dithiino [5,4-d]pyrimidine and benzylamine. The yield was 64% of theory.

Example 68 Using a procedure analogous to that described in Example 53, 6-morpholino-8-ethylamino-4H-m-dithiino[5,4- d] pyrimidine, M.P. 91-92 C. (recrystallized from ethanol), of the formula Using a procedure analogous to that described in Example 54, 6-morpholino-8-n-propylamino-4H-m-dithiino [5,4-d1pyrimidine, M.P. 9293 C. (recrystallized from ethanol), of the formula was prepared from 6-morpholino-8-chloro-4H-m-dithiino [5,4-d1pyrirnidine and n-propylamine. The yield was 70% of theory.

Example 70 Using a procedure analogous to that described in Example 52, -morpholino-8-n-butylamino-4I-I-rn-dithiino [5,4-djpyrimidine, M.P. 6869 C. (recrystallized from petroleum ether), was prepared from 6-morpholino-8- chloro 4H r1 dithiino[5,4-d]pyrirnidine and n-butylamine. The yield was 50% of theory.

Example 71 Using a procedure analogous to that described in Example 53, 6-(2-methyl-morpholino)-8-amino-4H-m dithiino[5,4-d]pyrimidine, M.P. 136137 C. (recrystallized from ethanol), was prepared from 6-(2-methylmorpholino) 8 chloro-4H-m-dithiino[5,4-d] pyrimidine and ammonia. The yield was 63% of theory.

Example 72 Using a procedure analogous to that described in Example 53, 6-pyrrolidino-8-amino-4H-m-dithiino[5,4-d] pyrimidine, M.P. 206207 C. (recrystallized from butanol), was prepared from 6-pyrrolidino-8-chloro-4H-mdithiino[5,4-d] pyrimidine and ammonia. 81% of theory.

The yield was Example 73 Using a procedure analogous to that described in Example 52, 6-pyrrolidino-8-n-propy1amino-4H-m-dithi- 22 ino[5,4-d]pyrimidine, M.P. 59-60 C. (recrystallized from ethanol), was prepared from 6-pyrrolidino-8-chloro- 4H-m-dithiino[5,4-d] pyrimidine and n-propylamine. The yield was 43% of theory.

Example 74 Using a procedure analogous to that described in Example 54, 6-mo1'pholino-8-isobutylamino-4H-1n-dithiino[5,4-d]pyrimidine, M.P. 124-125" C. (recrystallized from methanol), was prepared from 6-morpholino-8- chloro 4H m dithiino[5,4-d] pyrimidine and isobutylamine. The yield was 46% of theory.

Example 75 Using a procedure analogous to that described in Example 52, 6-morpholino-8-isoamylamino-4H-m-dithiino[5,4-d]pyrimidine, M.P. 93-94 C. (recrystallized from ethanol), was prepared from 6-morpholino-8- chloro 4H m dithiino[5,4-d] pyrimidine and isoarnylamine. The yield was 52% of theory.

Example 76 Using a procedure analogous to that described in Example 52, 6-(2'-methyl-morpholino) 8 isopropylamino-4H-m-dithiino[5,4-d]pyrimidine, M.P. l0010l C. (recrystallized from ethanol), was prepared from 6- (2' methyl-morpholino -8-chloro-4H-m-dithiino [5,4-d] pyrimidine and isopropylamine. The yield Was 43% of theory.

Example 77 Using a procedure analogous to that described in Example 52, 6-pyrrolidino-8-isopropylamino-4H-m-dithi ino[5,4-d]pyrimidine, M.P. 89-90 C. (recrystallized from ethanol), was prepared from 6-pyrrolidino-8-chloro- 4H m dithiino[5,4-d]pyrimidine and isopropylarnine. The yield was 67% of theory.

Example 78 Using a procedure analogous to that described in Example 52, 6-pyrrolidino-8-isobutylarnino-4H-m-dithiino[5,4-d]pyrimidine, M.P. 108109 C. (recrystallized from ethanol), was prepared from 6-pyrrolidino-8-chloro- 4H-m-dithiino[5,4-d1pyrimidine and isobutylamine. The yield was 76% of theory.

Example 79 Using a procedure analogous to that described in Example 54, 6-morpholino-8-allylamino-4H-m-dithiino [5,4-d]pyrimidine, M.P. 99100 C. (recrystallized from ethanol), of the formula o N-FN was prepared from 6-rnorpholino-8-chloro-4H-m-dithiino [5,4-d1pyrimidine and allylamine. The yield was 55% of theory.

Example 80 Using a procedure analogous to that described in Example 54, 6-pyrrolidino-8-allylamino-4H-m-dithiino [5,4-d]pyrimidine, M.P. 101 C. (recrystallized from ethanol), was prepared from 6-pyrrolidino-8-chloro- 4H-m-dithiino[5,4-d]pyrimidine and allylamine. The yield was 63% of theory.

Example 81 Using a procedure analogous to that described in Example 53, 6-morpholino-8-dimethylamino-4H-m-dithi 23 ino[5,4-d]pyrimidine, M.P. 115116 C. (recrystallized from ethanol), of the formula was prepared from 6-morpholino-8-chloro-4H-m-dithiino [5,4-d1pyrimidine and dimethylamine. The yield was 74% of theory.

Example 82 Using a procedure analogous to that described in Example 53, 6-(2-methyl-morpholino)-8-diethylamino- 4H-m-dithiino[5,4-d]pyrimidine, M.P. 9192 C. (recrystallized from ethanol), was prepared from 6-(2'- methyl-morpholino)-8-chloro 4H m dithiino[5,4-d] pyrimidine and diethylamine. The yield was 49% of theory.

Example 83 Using a procedure analogous to that described in Example 53, 6-pyrrolidino-8-diethylamino-4H-m-dithiino [5,4-d1pyrimidine, M.P. 8182 C. (recrystallized from ethanol), was prepared from 6-pyrrolidino-8-chloro-4H- m-dithiino[5,4-d] pyrimidine and diethylamine. The yield was 58% of theory.

Example 84 Using a procedure analogous to that described in Example 54, 6-morpholino-8-(diallylamino)-4H-m-dithiino[5,4-d]pyrimidine, M.P. 7374 C. (recrystallized from methanol), of the formula was prepared from 6-morpholino-8-chloro-4H-m-dithiino[5,4-d]pyrimidine and diallylamine. The yield was 56% of theory.

Example 85 Using a procedure analogous to that described in Example 54, 6-morpholino-8-(diethanolamino)AH-m-dithiino[5,4-d]pyrirnidine, M.P. 152153 C. (recrystallized from ethanol), of the formula was prepared from 6-morphilino-8-chloro-4H-m-dithiino- [5,4-d]pyrirnidine and diethanolamine. The yield was 41% of theory.

Example 86 Using a procedure analogous to that described in Example 54, 6-morpholino-8-(N-methyl-ethanolamino)-4H- m-dithiino[5,4-d]pyrimidine, M.P. l24125 C. (recrystallized from methanol), of the formula S la was prepared from 6-rnorpholino-8-chloro-4H-m-dithiino- [5,4-d1pyrimidine and N methyl ethanolamine. The yield was 64% of theory.

was prepared from 6-morpholino-8-chloro-4H-m-dithiino [5,4-d1pyrimidine and 3-methoxy-n-propylamine. The yield was'38% of theory.

Example 88 Using a procedure analogous to that described in EX- ample 54, 6-morpholino-8-(2-morpholinoethyl amino) 4H- -dithiin0[5,4-d]pyrimidine, M.P. 134136 C. (recrystallized from ethanol), of the formula NH-(CH2) s-N O was prepared from 6-morpholino-8-ch1oro-4H-m-dithiino [5,4-d] pyrimidine and 2-morpholinoethyl-amine. The yield was 57% of theory.

Example 89 Using a procedure analogous to that described in Example 55, 6-rnethyl-8-n-hexylamino-4H-m-dithiino[5,4-d] pyrimidine, M.P. 57 C. (recrystallized from petroleum ether), was prepared from 6-methyl-8-chloro-4H-m-dithiino[5,4-d]pyrimidine and n-hexylamine. The yield was 48% of theory.

Example 90 Using a procedure analogous to that described in Example 55, 6 methyl-8-pyrrolidino-4H-m-dithiino[5,4-d] pyrimidine, M.P. 131 C. (recrystallized from ethylacetate), was prepared from 6methyl-8-chloro-4H-m-dithiino[5,4-d] pyrimidine and pyrrolidine. The yield was 37% of theory.

Example 91 Using a procedure analogous to that described in Example 55, 6 methyl-8-morpholino-4H-m-dithiino[5,4-d] pyrimidine, M.P. 142-143 C. (recrystallized from ethylacetate), was prepared from 6-methyl-8-chloro-4H-m-dithiino[5,4-d]pyrimidine and morpholine. The yield was 40% of theory.

Example 92 Using a procedure analogous to that described in Example 55, 6-n-propyl-8-morpholino-4H-m-dithiino[5,4-d] pyrimidine, M.P. 74 C. (recrystallized from petroleum ether), was prepared from 6-n-propyl-8-chloro-4H-m-dithiino[5,4-d] pyrimidine and morpholine. The yield was 42% of theory.

Example 93 Using a procedure analogous to that described in EX- ample 55, 6-isopropyl-8-morpholino-4H-m-dithino[5,4-d] pyrimidine, M.P. 61 C. (recrystallized from petroleum ether), was prepared from 6-isopropyl-8-chloro-4H-m-dithiino[5,4-d] pyrimidine and morpholine. The yield was 58% of theory.

Example 94 Using a procedure analogous to that described in Example 52, 2-methyl-6,8-dimorpholino-4H-m-dithiino[5,4- d] pyrimidine, M.P. 147l48 C. (recrystallized from ethanol), was prepared from 2-methyl-6-morpholino-8- chl0ro-4H-m-dithiino[5,4-d]pyrimidine and morpholine. The yield was 70% of theory.

25 Example 95 Using a procedure analogous to that described in EX- ample 55, 2,6-dimethyl-S-rnorpholino-4H-m-dithiino[5,4- d]pyrimidine, M.P. 128 C. (recrystallized from ethylacetate), was prepared from 2,6-dimethyl-8-chloro-4H- m-dithiino[5,4-d] pyrimidine and morpholine. The yield was 32% of theory.

Example 96 Using a procedure analogous to that described in EX- ample 55, 2-methyl-6-ethyl-8-pyrrolidino-4H-m-dithiino [5,4-d1pyrimidine, M.P. 57-58 C. (recrystallized from petroleum ether), of the formula aiaf S was prepared from 2-methy1-6-ethyl-8-chloro-4H-m-dithiino[5,4-d]pyrimidine and pyrrolidine. The yield was 46% of theory.

Example 97 Using a procedure analogous to that described in EX- ample 55, 2-methyl-6-ethyl-8-morpholino-4H-m-dithiino [5,4-d1pyrimidine, M.P. 63 C. (recrystallized from petroleum ether), was prepared from 2-Inethyl-6-ethyl-8- chloro-4H-m-dithiino[5,4-d]pyrimidine and morpholine. The yield was 37% of theory.

Example 98 was prepared from 2-pheny1-6-pyrrolidino-8-chloro-4H- m-dithiino[5,4-d]pyrirnidine and morpholine. The-yield was 48% of theory.

Example 100 Using a procedure analogous to that described in Example 52, 2-phenyl-6,8-dimorpholino 4H m dithiino [5,4-d]pyn'midine, M.P. 128 C. (recrystallized from ethanol), was prepared from 2-phenyl-6-morpholino-8- chloro-4H-m-dithiino[5,4-d1pyrimidine and morpholine. The yield was 73 of theory.

Example 101 Using a procedure analogous to that described in EX- ample 55, 2-pheny1-6-methyl-8-morpholino-4H-m-dithiino [5,4-d1pyrimidine, M.P. 111-112 C. (recrystallized from petroleum ether), was prepared from 2-phenyl-6-methyl- 8-chloro-4H-m-dithiino[5,4-d1pyrimidine and morpholine. The yield was 50% of theory.

26 Example 102 Using a procedure analogous to that described in Example 56, 6-ethyl-8-morpholino-4I-Lrn-dithiino[5,4-d] pyrimidine maleate, M.P. 122 C. (recrystallized from ethylacetate), was prepared from 6-ethyl-8-chloro-4H-mdithiino[5,4-d]pyrimidine, morpholine and maleic acid. The yield was 56% of theory.

Example 103 Using a procedure analogous to that described in Example 55, 6-n-propyl-8-pyrrolidino-4H-m-dithiino[5,4-d] pyrimidine, M.P. 6768 C. (recrystallized from ethylacetate), was prepared from 6-n-propyl-8-chloro-4H-m-dithiino[5,4-d]pyrimidine and pyrrolidine. The yield Was 62% of theory.

Example 104 Using a procedure analogous to that described in Example 55, 6-n-propyl-8-piperidino-4H-m-dithiino[5,4-d]

pyrimidine, M.P. 61-62 C. (recrystallized from ethylacetate), of the formula was prepared from 6-n-propyl-8-chloro-4H-m-dithiino [5,4-d]pyrimidine and piperidine. The yield was 53% of theory.

Example 105 Using a procedure analogous to that described in EX- ample 56, 6-benzyl-8-morpholino-4H-m-dithiino[5,4-d]

pyrimidine hydrochloride, M.P. 213 C. (recrystallized from ethanol), was prepared from 6-benzyl-8-chloro-4H- m-dithiino[5,4-d]pyrimidine, mcrpholine and hydrochloric acid. The yield was 77% of theory.

Example 106 Using a procedure analogous to that described in EX- ample 55, 2-phenyl-6-isopropyl-8-n1orpholino-4H-m-dithiino[5,4-d]pyrirnidine, M.P. 138139 C. (recrystallized from ethylacetate), was prepared from 2-phenyl-6- isopropyl-8-chloro-4H-rn-dithiino[5,4 d] pyrimidine and morpholine. The yield was 64% of theory.

Example 107 Using a procedure analogous to that described in Example 53, 6,8-diamino-4H-m-dithiino[5,4-d1pyrirnidine,

M.P. above 320 C. (recrystallized from dirnethylforrnamide), of the formula was prepared from 6-amino-8-chloro 4H rn dithiino [5,4-d]pyrimidine and ammonia. The yield was 37% of theory.

Example 108 Using a procedure analogous to that described in EX- ample 53, 6-amino-S-morpholino-4H-m-dithiino[5,4-d] pyrimidine, M.P. 131.5 C. (recrystallized from ethanol), was prepared from 6-chloro-8-morpholino-4H- m-dithiino[5,4-d1pyrimidine and ammonia. The yield was 35% of theory.

Example 109 Preparation of 6-m0rplz0lin0-8-meth0xy-4H-m-ditlzlino [5,4-d1pyrimidine by Method B.5.8 gm. (0.02 mol) N J 66H:

were obtained. It had a melting point of 140-141 C.

AnaIysis.C H N O S mol. wt. 285.40. Calculated: C, 46.29%; H, 5.30%; N, 14.73%. Found: C,

Example 110 Using a procedure analogous to that described in EX- ample 109, 6-morpholino-8-ethoxy-4H-m-dithiino[5,4-d] pyrimidine, M.P. 122-123" C. (recrystallized from acetone), was prepared from 6-morpholino-8-chloro-4H-mdithiino[5,4-d] pyrimidine and sodium ethylate. The yield was 53% of theory.

Example 111 Using a procedure analogous to that described in Example 109, 6-morpho1ino 8 n propoxy-4H-m-dithiino [5,4-d]pyrimidine, M.P. 139 C. (recrystallized from acetone), was prepared from 6-morpholino-8-chloro-4H-dithiino[5,4-d] pyrimidine and sodium propylate. The yield was 71% of theory.

Example 112 Using a procedure analogous to that described in EX- ample 109, 6-morpholino-8-allyloxy-4H-m-dithiino[5,4-d] pyrimidine, M.P. 143144 C. (recrystallized from acetone), of the formula was prepared from 6-morpholino-8-chloro-4H-m-dithiino [5,4-d]pyrimidine and sodium allylate. The yield was 67% of theory.

Example 113 Using a procedure analogous to that described in Example 109, 6-pyrrolidino-8-ethoXy-4H-m-dithiino[5,4-d] pyrimidine, M.P. 91-92" C. (recrystallized from acetone), was prepared from 6-pyrrolidino-8-chloro-4H-m-dithiino [5,4-d1pyrimidine and sodium ethylate. The yield was 84% of theory.

Example 114 Using a procedure analogous to that described in Example 109, 6-pyrrolidino-8-isopropoXy-4H-m-dithiino[5,4- d] pyrimidine, M.P. 127128 C. (recrystallized from acetone), was prepared from 6-pyrrolidino-8-chloro-4H- m-dithiino[5,4-d] pyrimidine and sodium isopropylate. The yield was 59% of theory.

Example 115 Preparation of 6-(2-methyl-morpllolin0)-8-ethylamino 4H-m-dithiin0[5,4-d] pyrimidine hydrochloride from the free base.3.1 gm. (0.01 mol) of 6-(2methyl-morpholino) 8-ethylamino-4H-m-dithiino[5,4-d1pyrimidine were dissolved in 100 cc. of absolute ethylacetate, and the resulting solution was admixed with ethereal hydrochloric acid until it was acid to Congo Red. The precipitate formed thereby was separated by vacuum filtration, washed with absolute ethyl acetate and recrystallized from absolute 28 ethanol. 2.4 gm. (69% of theory) of the hydrochloride of 6- Zmethyl-morpholino) -8ethyl-amino-4H-m-dithiino [5,4-d]pyrimidine, M.P. 217-218" C., were obtained.

Analysis.C H ClN OS mol. wt. 348.93. Calculated: C, 44.75%; H, 6.07%; Cl, 10.16%. Found: C, 44.65%; H, 6.05%; Cl, 10.25%.

Example 116 Using a procedure analogous to that described in Example 2, 2-0-chlorophenyl-6-n-propyl-8 hydroxy-4H-mdithiino[5,4-d]pyrimidine, M.P. 230232 C. (recrystallized from methylglycol), of the formula was prepared from n-butyramidine hydrochloride and 2-0-chlorophenyl-4-carbethoxy-m dithianone (5). The yield was 59% of theory.

Example 117 Using a procedure analogous to that described in Example 2, 2-n-propyl-6-methyl-8-hydroxy-4H-mxlithiino [5,4-d]pyrimidine, M.P. 204-206" C. (recrystallized from ethanol), was prepared from acetamidine hydrochloride and 2-n-propyl-4-carbethoxy m dithianone-(S). The yield was 72% of theory.

Example 118 Using a procedure analogous to that described in EX- ample 2, 2-n-propyl-6-ethy1-8-hydroxy-4H-m-dithiino[5,4- d] pyrimidine, M.P. ISL-183 C. (recrystallized from ethanol), was prepared from propionamidine hydrochloride and 2-n-propyl-4-carbethoXy-m-dithianone-(5). The yield was of theory.

Example 119 Using a procedure analogous to that described in Example 2, 2,6-di-(n-propyl)-8-hydroXy-4H-m-dithiino[5,4- d] pyrimidine, M.P. 171173 C. (recrystallized from ethanol), was prepared from n-butyramidine hydrochloride and 2-n-propyl-4-carbethoXy-m-dithianone-(5). The yield was 70% of theory.

Example 120 Using a procedure analogous to that described in Example 3, 2-n-propyl-6-morpholino-8-hydroXy-4H-m-dithiino[5,4-d]pyrimidine, M.P. 232 C. (recrystallized from methyl-glycol), was prepared from N,N-diethyleneoxyguanidine hydrochloride and 2-n-propyl-4-carbethoxy-mdithianone-(S). The yield was 40% of theory.

Example 121 Using a procedure analogous to that described in Example 2, 2,2,6-trimethy1-8-hydroXy-4H-rn-dithiino[5,4-d] pyrimidine, M.P. 254257 C. (recrystallized from methyl-glycol), of the formula oar-K was prepared from acetamidine hydrochloride and 2,2- dimethyl-4-carbethoXy-m-dithianone-(5). The yield Was 68% of theory.

Example 122 Using a procedure analogous to that described in Example 2, 2,2-dirnethyl-6-ethyl-8-hydroxy-4H-m dithiino [5,4-d] pyrimidine, M.P. 227-230 C. (recrystallized from ethanol), was prepared from propionamidine hydrochloride and 2,2-dimethyl-4-carbethoxy-m-dithianone-(5 The yield was 60% of theory.

29 Example 123 Using a procedure analogous to that described in EX- ample 2, 6'-ethyl-8'-hydroXy-spiro[cyclohexane 1,2-(4H- m-dithiino[5,4-d1pyrimidine)], M.P. 230-233" C. (recrystallized from ethanol), of the formula was prepared from propionamidine hydrochloride and spiro-cycloheXane-l',2- [4-carbethoxy-m-dithianone (5)]. The yield was 60% of theory.

Example 124 Using a procedure analogous to that described in EX- ample 3, 6-dimethylamino-8-hydroXy-4H-m-dithiino[5,4- d] pyrimidine, IVLP. 285-288 C. (recrystallized from dimethylformamide), of the formula was prepared from N,N-dimethyl-guanidine hydrochloride and 4-carbethoxy-m-dithianone-(5). The yield was of theory.

Example 125 Using a procedure'analogous to that described in EX- ample 55, 2-n-propyl-6-methyl-8-pyrrolidino-4H-m-dithiino [5,4-d] pyrimidine, M.P 82-84" C. (recrystallized from acetone), was prepared from 2-n-propyl-6-rnethyl-8- chloro-4H-m-dithiino[5,5-d] pyrimidine and pyrrolidine. The yield Was 50% of theory.

Example 126 Using a procedure analogous to that described in EX- ample 55, 2-n-propyl-6-methyl-8-morpholino-4H-m-dithiino[5,4-d]pyrimidine, M.P. 87-89 C. (recrystallized from acetone), was prepared from 2-n-propyl-6-rnethyl- 8-chloro-4H-m-dithiino[5,4-d] pyrimidine and morpholine. The yield was of theory.

Example 127 Using a procedure analogous to that described in EX- ample 55, 2,2,6-trimethyl-8-pyrrolidino-4H-m-dithiino[5, 4-d]pyrimidine, MP, 112ll4 C. (recrystallized from petroleum ether), was prepared from 2,2,6-trimethyl-8- chloro-4H-m-dithiino[5,4-d]pyrimidine and pyrrolidine. The yield was 57% of theory.

Example 128 Using a procedure analogous to that described in EX- ample 55, 2,2,6-trimethyl-8-morpholino-4H-m-dithiino- [5,4-d] pyrimidine, M.P. 104 C. (recrystallized from acetone), was prepared from 2,2,6-trimethyl-8-chloro-4H- m-dithiino[5,4-d] pyrimidine and morpholine. The yield was 52% of theory.

Example 129 Using a procedure analogous to that described in Example 55, 2,2-dimethyl-6-ethyl-8-pyrrolidino-4H-m-dithiino[5,4-d]pyrimidine, M.P. ll5-117 C. (recrystallized from methanol), was prepared from 2,2-dimethyl-6-ethyl- 8-chloro-4H-m-dithiino[5,4-d1pyrimidine and pyrrolidine. The yield was 58% of theory.

Example 130 Using a procedure analogous to that described in Example 55, 2,2-dimethyl-6-ethyl-8-morpholino-4H-m-dithiino[5,4-d] pyrimidine, M.P. 81-83 C. (recrystallized from acetone), was prepared from 2,2-dimethyl-6-ethyl-8-chloro-4H-m-dithiino[5,4-d1pyrimidine and morpholine. The yield was 35% of theory.

Example 131 Using a procedure analogous to that described in EX- ample 5 6, 2,2-dirnethyl-6-n-propyl-8-morpholino-4H-m-dithiino[5,4-d]pyrimidine maleate, M.P. 100-101 C. (recrystallized from ethylacetate), was prepared from 2,2- dimethyl 6 n-propyl-8-chloro-4H-m-dithiino[5,4-d]pyrimidine, morpholine and maleic acid. The yield was 64% of theory.

Example 132 Using a procedure analogous to that described in EX- ample 55, 6-methyl-8-pyrrolidino-spiro[cyclohexane-1,2'- (4H-m-dithiino[5,4-d]pyrimidine)], M.P. C. (recrystallized from acetone), of the formula was prepared from 6'-rnethyl-8-chloro-spiro[cyclohexane- 1,2'(4H-rn-dithiino [5,4-d1pyrimidine) and pyrrolidine. The yield was 38 of theory.

Example 133 Using a procedure analogous to that described in EX- ample 55, 6'-methyl-8-morpholino-spiro[cyclohexane-l, 2-(4H-m-dithiino[5,4-d1pyrirnidine)], MP. 88-91" C. (recrystallized from petroleum ether), of the formula GE W was prepared from 6-methyl-8-chloro-spiro[cyclohexanel,2- (4H-11-dithiino [5 ,4-d] pyrimidine) and morpholine. The yield was 41% of theory.

The compounds according to the present invention, that is, those embraced by Formula I above, their non-toxic, pharmacologically acceptable acid addition salts and their alkali metal salts, have useful pharmacodynamic properties. More particularly, they exhibit sedative, analgesic, antiphlogistic, antipyretic and cardiovascular activities. In addition, they are useful as intermediates in the preparation of pesticidal compoundsv For pharmaceutical purposes, the compounds of the present invention are administered topically, parenterally or orally as active ingredients in customary dosage unit compositions, that is, in compositions in dosage unit form consisting essentially of an inert pharmaceutical carrier having uniformly distributed therein one dosage unit of the active ingredient, such as tablets, pills, solutions, suspensions, suppositories and the like. One dosage unit of the compounds of the present invention is from 10 to 200 mgm., preferably 25-50 mgm.

The following examples illustrate a few dosage unit compositions comprising a compound of the present invention as an active ingredient, The parts are parts by weight unless otherwise specified.

Example 134 Coated pills.--The pill cores are compounded from the following ingredients:

compound, the calcium phosphate and the corn starch are admixed with each other, the mixture is moistened with an aqueous 14% solution of the gelatin, the moist mixture is forced through a 1.5 mm.-mesh screen, and the resulting granulate is dried at 40 C. The dry granulate is forced through a 1.0 mm.-mesh screen, admixed With the talcum and the magnesium stearate, and the mixture is pressed into 130 mgm.-pill cores. The pill cores are then coated with a thin shell consisting essentially of talcum and sugar, and the coated pills are polished with beeswax. Each pill weighs about 200 mgm. and contains 25 mgm. of the active ingredient.

Example 135 Hypodermic solntion.The solution is compounded from the following ingredients:

Parts 6-pyrrolidino-8-(4'-methyl-piperazino) 4H mdithiino [5,4-d] pyrimidine 10.0 Tartaric acid 10.0 Polyethyleneglycol 600 100.0 Distilled water q.s. ad 1 2000.0

1 By volume.

Compounding procedure-T he polyethyleneglycol is melted and is admixed With about twice its volume of distilled water. The mixture is heated to 80 C., and then the tartaric acid and the dithiino pyrimidine compound are successively dissolved therein. The solution is allowed to cool to room temperature, is diluted with additional distilled Water to the desired volume, and is finally filtered until free from suspended particles. The filtered solution is filled into brown 2 cc.-ampules which are then sterilized for thirty minutes at 100 C. and sealed. Each ampule contains 10.0 mgm. of the active ingredient.

Example 136 Drop solution-The solution is compounded from the following ingredients:

Parts 6-pyrrolidino-8-diethylamino-4H-m dithiino[5,

4-d]pyrimidine 10.0 Tartaric acid 10.0 Cane sugar 350.0 Sorbic acid 1.0 Essence of cocoa 50.0 Ethanol 1 200.0 Polyethyleneglycol 600 1 100.0 Distilled water q.s. ad 1 1000.0

By volume.

Compounding procednra-The sorbic acid is dissolved in the ethanol, an equal amount of Water is added, and then the tartaric acid and the dithiino pyrimidine compound are dissolved therein while stirring (Solution A). The cane sugar is dissolved in the remaining amount of distilled water (Solution B). Solution B, the polyethyleneglycol and the essence of cocoa are added to Solution A while stirring, and the finished solution is filtered. Each cc. of the solution (about five drops) contains 10 mgm. of the active ingredient.

s2 Example 137 TabIets.The tablet composition is compounded from the following ingredients:

Parts 2meth;. l-6-n-propyl-S-morpholino -4 H m dithiino[5,4-d1pyrimidine 50.0 Lactose 80.0 Potato starch, dry 16.0 Polyvinylpyrrolidone 10.0 Potato starch, undried 10.0 Colloidal silicic acid a- 2.0 Magnesium stearate 2.0

Total 170.0

Example 138 Suppositories.--The suppository composition is compounded from the following ingredients:

Parts 2-methyl-6-ethyl-8-morpholino-4H-m dithiino[5,

4-d] pyrimidine 200.0 Cocoa butter 1550.0

Total 1750.0

Compounding procednre.The cocoa butter is melted and cooled to 37 C., the finely pulverized dithiinopyrimidine compound is stirred in, and the resulting suspension is homogenized and then poured into cooled suppository molds, each holding 1750 mgm. of the suspension. Each suppository contains 200 mgm. of the active ingredient.

Example 139 Gelatin capsules.The capsule filling is compounded from the following ingredients:

Parts 2-isopropyl-6-methyl-8-hydroxy-4H-m dithiino[5,

4-dlpyrimidine 20.0 Lactose 60.0 Talcum 20.0

Total 100.0

Compounding procedure-The individual ingredients are intimately admixed with each other, the mixture is passed through a 1.0 mm.-mesh screen, and the screened mixture is filled into gelatin capsules, each holding mgm. of the mixture. Each capsule contains 20 mgm. of the active ingredient.

Although the above dosage unit composition examples illustrate only a few of the clithiino[5,4-d]pyrimidine of the present invention as active ingredients, it should be understood that any of the other compounds embraced by Formula I or their non-toxic acid addition salts or their alkali metal salts may be substituted for the illustrated active ingredient species in Examples 134-139. Similarly, the amount of active ingredient may be varied within the dosage unit limits set forth above, and the nature and amounts of the inert adjuvants may be varied to meet particular requirements.

While the present invention has been illustrated with the aid of certain specific embodiments thereof, it will be readily apparent to others skilled in the art that the invention is not limited to those specific embodiments and that various changes and modifications may be made 33 Without departing from the spirit of the invention or the scope of the appended claims.

We claim: 1. A compound selected from the group consisting of 4H-m-dithiino[5,4-djpyrimidine substitution products of the formula wherein R and R are each selected from the group consisting of hydrogen, lower alkyl, phenyl, halophenyl, benzyl and, together with each other and the carbon atom to which they are attached, a spirocyclic ring of a formula selected from the group consisting of KI I R is selected from the group consisting of hydrogen,

lower alkyl, lower alkoxy, phenyl, benzyl and wherein R and R together with each other and the adjacent nitrogen atom, form a basic heterocyclic ring selected from the group consisting of pyrrolidino,, morpholino and lower alkyl-morpholino, and R is selected from the group consisting of hydroxy, lower alkoxy, lower alkenoxy and wherein R and R are each selected from the group consisting of hydrogen, lower alkyl, phenyl, halophenyl, benzyl and, together with each other and the carbon atom to which they are attached, a spirocyclic ring of a formula selected from the group consisting of R is selected from the group consisting of hydrogen,

lower alkyl, lower alkoxy, phenyl, benzyl and wherein R and R together with each other and the adjacent nitrogen atom, form a basic heterocyclic ring selected from the group consisting of pyrrolidino, morpholino and lower alkyl-morpholino,

34 and their non-toxic, pharmacologically acceptable acid addition salts.

3. A compound selected from the group consisting of 4H-m-dithiino[5,4-d]pyrimidine substitution products of the formula O-lower alkyl wherein R and R are each selected from the group consisting of hydrogen, lower alkyl, phenyl, halophenyl, benzyl and, together with each other and the carbon atom to which they are attached, a spirocyclic ring of a formula selected from the group consisting of KQ I R is selected from the group consisting of hydrogen,

lower alkyl, lower alkoxy, phenyl, benzyl and wherein R and R together with each other and the adjacent nitrogen atom, form a basic heterocyclic ring selected from the group consisting of pyrrolidino, morpholino and lower alkyl-morpholino, and their non-toxic, pharmacologically acceptable acid addition salts.

4. A compound selected from the group consisting of 4H-m-dithiino[5,4-d1pyrimidine substitution products of the formula N Rs( S wherein R and R are each selected from the group consisting of hydrogen, lower alkyl, phenyl, halophenyl, benzyl and, together with each other and the carbon atom to which they are attached, a spirocyclic ring of a formula selected from the group consisting of R is selected from the group consisting of hydrogen,

lower alkyl, lower alkoxy, phenyl, benzyl and wherein R and R together with each other and the adjacent nitrogen atom, form a basic heterocyclic ring selected from the group consisting of pyrrolidino, morpholino and lower alkyl-morpholino, and

R and R are each selected from the group consisting of hydrogen, lower alkyl, lower alkenyl, hydroXy-lower alkyl, lower alkoXy-lower alkyl, morpholino-lower alkyl, phenyl, benzyl, cyclohexy and, together with each other and the adjacent nitrogen atom, a basic heterocyclic ring selected from the group consisting of pyrrolidino, morpholino, piperidino, lower alkyl-morpholino and N'-lower alkyl-piperazino,

and their non-toxic, pharmacologically acceptable acid addition salts.

5. 6,8-dimorpholino-4H-m-dithiino [5,4-d] pyrimidine.

6. 6 pyrrolidino 8-morph01in0-4H-rn-dithiino[5,4-d] pyrimidine.

7. 6 pyrrolidino 8-(4-methy1piperazino)-4H-m-dithiino[5,4-d]pyrimidine.

8. 6 pyrrolidino-8-diethy1amino-4H-m-dithiin0[5,4-d] pyrimidine.

9. 6 n propyl-8-morpholino-4H-m-dithiino[5,4-d] pyrimidine.

10. 2 methyl 6-n-pr0py1-8-morpho1ino-4H-m-dithiinc [5 ,4-d pyrimidine.

11. 2 methyl 6-ethyl-8-m0rpho1ino-4H-m-dithiin0 [5,4-d] pyrimidine.

12. 2 i pr0pyl-6-methy1-8-hydroxy-4H-m-dithiino [5,4-d] pyrimidine.

13. 2 n propy1-6-morpho1ino-8-hydroxy-4H-m-dithiino 5,4-d] pyrimidine.

36 References Cited by the Examiner UNITED STATES PATENTS OTHER REFERENCES Howard et aL: J.A.C.S., vol. 82, pp. 158-64 (1960).

WALTER A. MODANCE, Primary Examiner.

R. T. BOND, Assistant Examiner. 

1. A COMPOUND SELECTED FROM THE GROUP CONSISTING OF 4H-M-DITHIINO(5,4-D)PYRIMIDINE SUBSTITUTION PRODUCTS OF THE FORMULA 